Add release script (#49)

Author: f-f

release.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+# Please use this script to cut new releases.
+# It will create a tag and push it, which will trigger CI to create a release,
+# build release files, push them to the release, and publish a new version on NPM
+
+NEW_TAG=v$(jq -r ".version" package.json)
+
+# Fail if the new tag already exists
+if git rev-parse "${NEW_TAG}" >/dev/null 2>&1; then
+  echo "Tag '${NEW_TAG}' already exists, please bump the version in package.json";
+  exit 1;
+fi
+
+echo "Creating and pushing new tag '${NEW_TAG}'.."
+
+git tag "${NEW_TAG}"
+
+git push origin "${NEW_TAG}"
+
+echo "Done."
+